Lock



Apr. 24, 1923. 1,452,812

. E. MURMANN LOCK ` Filed May 2, 1922 2 Sheets-Sheet l IN VEN TOR.fafa/7e@ //z/r/m/f/l J/ ATTORNEYS.

Apr. 24, 1923. 1,452,812

E.`O. MURMANN y LOCK Filed May 2, 1922 2 Sheets-Sheet 2 n INVENToR.@ye/7@ /W/ffa/y/f BY Wma ..e MQ

A TTORNEYS.

Patented Apr.. 24, 1923.

1T ST EUGENE O. MURMANN, OF GLENDALE, CALIFORNIA.

LOCK.

Application inea May 2, 1922. serial No. 557,946'.

, To all whom t 'may concern.'

Be it known that'I, EUGENE 0. MURMANN, a citizen of the United States,and resident of Glendale, in the county of Los Angeles and State ofCalifornia, have inventcdnew and useful Improvements in a Lock, of whichthe following is a specification. A This invention relates to a cylinderlock and pertains especially to a lock having a plug rotatable within aplurality of transversely movable plate tumblers. lt is the primary4object of this invention to provide a construction of the classdescribed which may be made compact, is simple, durable, and easilyassembled. In addition to the broader objects of this invention, thereare several novel features of construction hereinafter set forth andcorresponding accomplishments secured thereby.

The invention is illustrated, by way of example, in the accompanyingdrawings, in which:

Fig. 1 is a perspective view of a complete lock housed within a casing,a portion of the casing being broken away to better show the parts; Fig.2 is an enlarged fragmental section showing the key in position; Fig. 3is y a section similar to Fig. 2 showing the key removed; Fig. 4 is asectionthrough the lock and casing and a fragment of adoor, the keybeingshown in position with the bolt drawn back; Fig. 5 is a perspectiveview of a fragment of the lock with the casing partially broken away andparts is shown in section; Fig. 6 is a perspective view of the plug;Fig. 7 is a perspective view ofl one of the tumbler plates; Fig. 8 is aperspective view of one of the alignment washers; and Fig. 9 is aperspective view of the plug, a tumbler plate and its aligningwasher,with the parts in locking position.

In the drawing, the lock is shown housed Within a casing adapted to beinserted in a cylindrical recess in a door. plates 10 and 11 are bent attheir ends, and

clamped therebetween is a center plate 12.l

At the outer ends, the foundation plates are secured to a selvage plate14. Mountedk in a latch opening in the selvage is a latch 15. The latchhas secured thereto aprons 17 and 18. These aprons serve to complete thehousing for aspring 19 extending overy a tongue 20 on the center plate12. 0A tongue 21 is cut from the apron 17 and bent downwardly. A similartongue in a corresponding position is provided on the plate 18 forFoundation engagementby rock levers 22 and 23. A projection 24 forengagement by the shank of a knob is connected to rock lever 22.

In installing the lock, a cylindrical recess 25, see Fig. 4, is boredinto the door from the edge and isv met by a bore 26 extending throughthe door from one side to the other. The bore v26 is positioned in thedoor at the p oint at which a key would be inserted. A circular plate27, has legs 28 straddling the casing. The plate has a bevelled edge asindicated by 29 and rests within a flanged collar 30 which completes thecover for one end of the bore 26. Plate 27 has `a key hole. The feet oflegs 28 are bored and threaded to receive screws whichy passv through avcover plate 31. Cover plate 31 carries a knob 32 mounted on a shank 33.The shank has a kerf to receive projection 24. It is obvious that bytightening the screws, the parts may be securely held in'position.Turning knob will causey lever 22 to be rocked, the lat* ter engaging atongue, as indicated by 21 and moving aprons 17 and 18 inwardly againstthe action of spring 19 so as to retract the latch bolt 15. The samemovement may be accomplished by rocking lever 23 which is operated bymeansof a key.

The lock mechanism is mounted between center plate 12 and foundationplate 10. Extending from plate 10 are guides 34 and 35. Slidably mountedbetween the c guides 34 are tumbler plates.y In this case' four tumblesplates are shown. These tumbler plates are identical,- being rectangularand having an opening comprising a circle 37 intersected by a rectangleso as to form oppositely disposed wing recesses 38, see Fig. 7. A

plug 39 has opposite arcuate faces corresponding to the circle 37 in thetumbler plates and of such dimensions that when the plug is aligned atthe centers of the tumbler plates it may be rotated. The plug is alsoprovided with opposite flat faces so that it may slide in the wings 38as indicated in Fig. 9. A key hole 40 is formed in the plug and thelatter is preferably constructed of two sections 41 and 42 which aremilled on opposite faces to form a keyhole when brought together.l Thesections are held in position by the lever 33 and a washer 43. Thus, inmanufacturing the lock, long barsy may be milled out and then cut intorplufr lengths. Transverse kerfs 44, see Fig. 6, of the same depths arecut into the plugto intersect the keyhole. These are arranged to receivealignment Washers 45. These washers are circular and of the same size asthe circular openings 37 in the tumbler plates so that when properlyaligned they may be rotated therein. They have a plug opening ofrectangular orm indicated by 4G in Fig. 8. The depth of the chordalpartl 4T of the Washer is made to differ for different Washers. TheWashers are slipped into position in the kerfs 44 so as to ride for alimited distance back and forth. It is obvious that Whenin positionvvith the chordal parts extending into the kerfs 44 or' the plug, thatthe peripheries olf the alignment Washers Will not be in the surface oi'a single cylinder. Each tumbler plate is positioned over a washer, andif the Washer is not in position to form a cylinder with the arcuatesurfaces of the block, the tumbler plates. will be moved so that theplug is disposed in one of the Wings as shown in F ig. 9. In thisposition the plug could n ot be rotated. A multiple finger spring 4S ispositioned so as to press against each one of the tumbler plates and tomaintain them in the position such that the chordal parts of the Washers45 are moved into their kerfs 44 in the plug as far as they Will go.This results in the tumbler plates being positioned With their circularrecesses 37 out of line and the plug 39 resting in the Wings. In thisposition the plug cannotrbe turned. If a key is inserted in the keyholeand engaged with the chordal portions of the Washer 45 to kmove thelatter into position so that they align and the plug and Washer are inthe surface of a cylinder, then the tumbler plates Will be moved to aposit-ion such that thecircular recesses 37 are in line permitting theplug to be rotated.

In Fig. 3 tie tumbler plates are thrown out of alignment. In Fig. 2 akey 50 is shovvn in the keyhole. .The edge of the key is of suchconfiguration that when fully inserted, it Will align the Washers andthe recesses in the tumbler plates so that the plugs may be turned. InFig. 4 the plug is shown turned into position so that the latch bolt isdrawn back. Just as soon as the key is removed, the tumbler plates aremoved to locked position.

What I claim is:

l. In a lock, the combination of a casing, a movable plate-tumblerhaving an opening comprising a circle intersected by a rectangle, a plugrotatable When centered in the circular part of said opening andnonrotatable When disposed in the rect-angular part and eccentric to thecircular part of 4said opening, key operated means for moving saidtumbler to align the circular part of said opening to permit rotation ofsaid plug, and means tending to move said tumbler out of alignment.

2. In a lock, the combination of a casing, a plurality of independentlymovable platetumblers each having an opening comprising a circleintersected by a rectangle, a plug rotatable when centered in thecircular parts of said openings and non-rotatable when disposed in therectangular parts and eccentric to the circular parts of said openings,key operated means for moving said tumblers to align, the circular partsof said openings and permit rotation of said plug, and means tending tomove said tumblers out of alignment.

3. In a lock, the combination of a casing, a movable plate-tumblerhaving an opening comprising a circle intersected by a rectangle, a plugrotatable when centered in the circular part of said opening andnon-rotatable when disposed in the rectangular part and eccentric to thecircular part of said opening, an alignment Washer having a circularperiphery fitting Within the circular part of said opening and slidablymounted on said plug, and key operated means for moving said Washer andsaid tumbler so as to center the latter Within the opening in saidtumbler and permit rotation, and means tending to move said tumbler outof alignment.

4. In a lock, the combination of a casing, a plurality ot independentlymovable platetumblers each` having an opening comprising a circleintersected by a rectangle, a plug rotatable ivhen centered in thecircular parts of said openings and non-rotatable When disposed in therectangular parts and eccentric to the circular parts of said openings,alignment washers having circulaiperipheries fitting Within the circularparts of said openings and riding on said plug,

kkey operated means fon moving said tumblers to align the circular partsof said openings and permit rotation of said plug,.and means tending tomove said tumblers out olI alignment.

5. In a lock, the combination of a casing, a movable plate-tumblerhaving an opening com rising a circle intersected by a? rectang e, aplug` rotatable When centered in' the circular part of said opening andlnonrotatable when disposed in the rectangular part and eccentric to thecircular part of said opening, said plug having a keyhole and a kerfintersecting said hole in line with said tumbler, an alignment Washerhaving a circular periphery fitting Within the circular part or' saidopening and riding in said kerf, said washers having a chordal partabutting said plug, and means tending to move said tumbler transversely.

6. In a lock, the combination of a casing, aplurality of independentlymovable plate-tumblers, each having an opening comprising a circleintersected by a rectangle, a plug rotatable When centered in thecircular parts of said openings and nonrotatable when disposed in therectangular Til parts and' eccentric to the circular parts of saidopenings, said plug having, a keyhole and kerfs intersecting saidkeyhole in line with said tumblers, alignment Washers hav- 5 ingcircular peripheries fitting Within the circular parts of said openingsand riding in said kerfs, said Washers having chordal parts of varying`depths, and means tending to move said tumblers transversely.

In Witness that I claim the foregoing I 15 have hereunto subscribed myname this 24th day of April, 1922.

EUGENE O. MURMANN.

